Lock-nut.



H. DOLLMAN. LOOK NUT. APPLICATION FILED OUT; 31, 1913.

1,113,419. Patented Oct. 13, 1914.

WiZnwses: I i'v/wnlor 4% 40M MJMW I 7/10 WW 7% HUBER/I. DOLLMAN, OF BIRMINGHAM, ENGLAND.

Look-NUT.

Specification of Letters'l'atent.

Application filed October 31, 1913. Serial No. 798,438.

. Lock-Nuts, of which the following is a specification.

Th1s invention comprises an improved lock-nut which is so constructed as to be effectually prevented from turning back under the influence of vibration.

My improved lock nut can be effectively employed with an ordinary threaded bolt, and is so constructed that the locking piece of the nut is wholly disposed within the periphery of the body of the nut, so that it cannot be acted upon by the spanner or wrench.

According to this invention the outer por- I tion of the nut is formed as a pair of spring tongues having their free ends adjacent and pointing toward each other, said tongues being adapted to act radially or thereabout to the nut axis and grip the boltwhen the nut is screwed thereon, said tongues being so located on the nut that they are not affected by the application of a spanner thereto. By preference the nut is made of steel and the spring tongues are hardened and tempered, although they may be left unhardened.

Of the accompanying drawings, Figure 1 is a front elevation of a hexagonal nut constructed in accordance with this invention; Fig. 2 is a plan of the same; Fig.3 is a side elevation of the same, and Fig. 4 is a sectional front elevation on line of Fig. 2.

My invention is applicable to all kinds of lock-nuts whether of round, square, hexagonal, octagonal or other shape.

In carrying out' my invention the nut.

bla-nkis formed with an eccentric circular pommel projecting from its outer face and before or after the nut has been tapped through this pommel the latter is divided at its thinnest part by a cross saw-cut 1 ex tending from the top of the pommel down to the face of the nut and then this pommel is almost separated from the face of the nut by a horizontal saw-cut or division 2 taken pommel into two spring tongues marked respectively 3, 4 which are connected to the nut proper by the solid part 8 which has not been removed by the horizontal saw-cut. Owing to the pommel being eccentric the spring tongues 3, 4 taper from their root part 8 to their free ends 5, 6. These free ends 5, 6 of the two tongues 3, 4 are pressed slightly inwardly so that the internal diameter of the bolt hole between the spring tongues is smaller than the internal diameter of the bolt hole in the body portion of the nut by an amount sufiicient to cause each tongue to exert a gripping pressure on the bolt when the nut is screwed thereon, the

sharp angular corners 9 of the free ends 5, 6

of the tongues 3, 4 being by preference taken ofl to prevent them from injuring the threads of the bolt. The tongues 3, 4 are or may be conveniently hardened and tempered to the required degree so that they have a Patented Oct. 13, 1914.

of lock-nut above described the application .of a spanner thereto for the purpose of turning 'it does not damage the spring tongues 3, 4 owing to their being nearer to the nut axis than are the faces 7 of the body of the nut which are engaged by the spanner.

What I claim as my invention and desire to secure by Letters Patent is A lock nut having a thread formed therein and consisting of a body portion and a locking piece comprising two are shaped spring tongues eccentricallv disposed to the axis of the nut and extending around more than three fourths of the circumference of the bolt hole, said tongues being connected to said body portion at one part only, said tongues being integral with the body portion and -with each other and formed by two right angle saw cuts, said locking piece being disposed wholly within the periphery of In testimony whereof I have signed my sald body portion, the thread in said body name to this specification in the presence of portion being of uniform diameter throu htwo subscribing witnesses.

out, and the thread in said locking piece e- HUBERT DOLLMAN. ing of uniform diameter throughout and Witnesses: being of less diameter than the thread in CHARLES BoswoR'rH KETLEY,

said body portion. ELIZABETH MAY DUDLEY. 

